Abstract: Chinese sturgeon (Acipenser sinensis) juveniles were cultured at the water temperature 15, 20, 25, and 30 ℃ for 66 days to study the effects of different water temperature on the blood biochemical parameters of the juveniles,  including total protein (TP), albumin (ALB), glucose (GLU), total cholesterol (TC), triglyceride (TGL), high density lipoprotein cholesterin (HDLC), total bilirubin (T-BIL), and urea. With the increase of water temperature, the concentrations of TP, ALB, GLU, TC, and HDLC in the blood all increased first and decreased then, and reached the maximum at 20 ℃, with the values being 15.98 g·L^-1, 5.6 g·L^-1, 4.85 mmol·L^-1, 2.44 mmol·L^-1, and 0.61 U·L^-1, respectively. The concentrations of blood TP, ALB, GLU, TC, and TGL reached the minimum at 30 ℃, and the values were 8.93 g·L^-1, 3.1 g·L^-1, 2.26 mmol·L^-1, 1.34 mmol·L^-1, and 3.35 mmol·L^-1, respectively. The T-BIL concentration also increased first and decreased then, with the maximum (2.50±0.84 mmol·L^-1) at 15 ℃ and the minimum (1.65±0.10 mmol·L^-1) at 25 ℃. Urea concentration decreased significantly with increasing water temperature, being the lowest (0.54±0.36 mmol·L^-1) at 30 ℃. The variation patterns of the blood biochemical parameters suggested that at 20 ℃, juvenile Chinese sturgeon had lower energy expenditure, being optimal for its growth.

Key words: Nitrogen fertilizer, Helicoverpa armigera, Aphid gossypii, Cotton yield